A Study to Examine the Safety and Tolerability of Single Ascending Doses of REGN2477

Inclusion criteria

• Healthy women not of childbearing potential between 18 and 65 years of age, with no significant health issues or clinically significant abnormal laboratory findings
• A body mass index (BMI) between 18 to 30 kg/m2, inclusive
• Provide a signed informed consent

Exclusion criteria

• Significant illness or history of significant illness
• Clinically significant abnormal CBC, clinical chemistry, and urine analysis at screening
• Current smoker or former smoker who has stopped smoking within 3 months prior to screening
• Positive urine drug test results during screening, or history of drug or alcohol abuse
• Donation or loss of, blood within 8 weeks prior to screening, or plasma up to 14 days prior to screening
• History of diabetes
• Abnormal blood pressure (BP)
• History of gynecological disorders or malignancies; history of breast malignancies; or history of benign gynecological or breast lesions that require medical treatment or follow up
• Reduced renal function
• Known history of chronic hepatitis or HIV
• Clinically significant ECG abnormalities
• Participation in any clinical research study within 30 days, or 5 halflives, of the study drug, whichever is greater, or for longer periods per regional requirements, prior to the screening visit
• Exposure to any biological drugs within 3 months of the screening visit (the name of the drug and duration of previous exposure will be recorded). Vaccination within 4 weeks of screening visit.
• History of hypersensitivity reactions to vaccines or other biologics
• History of hypersensitivity to doxycycline or other tetracycline antibiotics
• History of osteoporosis requiring osteoporosis treatments such as PTH, bisphosphonates, and denosumab
• Subject using hormone replacement therapy or thyroid replacement therapy will be excluded, unless they have been on stable doses of such therapy for at least 6 months and will remain on the same stable dose through the duration of the trial
• Use of systemic glucocorticoids, including oral glucocorticoids, for more than 10 days, within 3 months prior to screening.